Device and method for applying precise irrigation, aspiration, medication, ultrasonic power and dwell time to biotissue for surgery and treatment

ABSTRACT

Apparatus and method for applying aspiration, irrigation, medication and ultrasonic power and dwell time to biotissue for surgery and treatment wherein the pressure for both aspirating and irrigating is precisely and accurately maintained by the use of a differential valve and a control reservoir which is generally much larger than the biotissue cavity to be operated on and wherein the pressures for irrigation, apiration, medication and the application of the amplitude and dwell time of ultrasonic energy can be precisely controlled, externally, to the patient.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates in general to a device and method for applyingprecise irrigation, aspiration, medication, ultrasonic power and dwelltime to biotissue for surgery and treatment and in particular to animprovement on and in addition to the device disclosed in our U.S. Pat.No. 3,990,452 which issued on Nov. 9, 1976.

2. Description of the Prior Art

Substantial experience during operations in medical operating roomsusing the ultrasonic equipment shown in our U.S. Pat. No. 3,990,452which issued on Nov. 9, 1976 has disclosed that the needs of surgeonsfor providing proper operating room care to patients is far more complexand difficult than was a first realized by those supplying aspirating,irrigating and ultrasonic equipment. For example, prior art devices areon the market which includes complex aspirators and irrigators forremoving fluids from body cavities such as the eye, lungs, veins,kidneys and other organs; yet, very few physical--as opposed tophysiological--in situ, measurements have been made in these cavitiessuch as the pressures and flow rates therein, and litte if any efforthas been made to provide precise flow and pressure control when workingin such body cavities.

This some situation exists for infusing medicine or treatment fluids tobathe (lavage) or flood tissue on a controlled basis at the invasionsite as is required by the attendant doctors.

When ultrasound is additionally used there has been concern about theexposure of the tissue to the radiation and occasionally to its heatingeffect, yet few if any instruments in use today have been able tomeasure the true power in watts per unit of time, or in other words, thetime rate of doing work applied to the tissue. The reason for this isnot because this data is not necessary and required but due to the factthat the instrumentation has not been available heretofore to obtain orcontrol this unique form of energy.

Another discovery was that the same equipment used for irrigation,aspiration and applying measured ultrasonic power to biological tissuesfrequently must also apply medication such as drugs or treatment fluids,for example, to the cavity or tissue being invaded in a manner similarto the heart-lung machine wherein the medicines are supplied to themachine rather than directly to the patient.

Our study has illustrated that a total consideration of the problemrequires analysis of at least the following areas:

a. Irrigation

b. Aspiration

c. Medication

d. Power Control

e. Duration Control

f. Supplementary Devices

For simplicity, it is assumed that the ultrasonic medical devicedescribed in our U.S. Pat. No. 3,990,452 will be used in the proceduresdescribed.

Definitions are where possible taken from Stedman's Medical Dictionary,22 nd Edition.

A. Irrigation--(The washing out of a cavity or wound surface with astream of fluid.)

The present art discloses bottles, flasks, retorts, tanks, etc., whichare elevated or hanging, pressurized and so forth. All of these have onecommon feature for medical work and that is that they must containsterile treatment or lavaging fluid so as to make it available to theattendants as needed. A great deal of ingenuity has gone into devisingirrigation systems, some being very complex such as the closed cycle,blood circulatory system of the heart/lung machine; while others are assimple as a hanging I.V. bottle which has been used at least since 1902.

Some systems which use the hanging bottle are able to simultaneouslycreate positive and negative pressure (vacuums) without the use ofmechanical pumps by simply making use of the variation in atmosphericpressure over short elevational heights of several hanging bottles in astepped series. Pumps and hand held syringes have also been used forirrigation purposes.

The inventors have discovered that the problem of irrigating tissue isbasic and that you must meet several needs of the medical situation suchas:

1. The system must be sterile and maintain its sterility which means itshould not be open to the air, in other words, it must be a closedsystem.

2. It must provide irrigating fluid at whatever controllable pressure isneeded.

3. It must provide whatever flow/volume rate is needed at that chosenpressure.

4. It must provide the fluids in the total volume and at the temperatureneeded by the patient as decided by the surgeon or technician present.

5. The system must be reliable so that it will not fail.

Additional to these absolute must-do features, the system should alsodesirably include the following features:

1. Be easy to clean to medical standards.

2. Be easy to set up and use.

3. Be reasonably priced, and

4. Be extremely reliable.

It is not always possible to accomplish all of the desirable featuresbut the absolutely required features listed under 1 through 5 above mustalways be accomplished.

Our study has indicated that too many of the desirable features havebeen provided in irrigation systems while some of the absolutelyrequired features have not been provided. For example, many devices aremade of throw-away, one-time use, plastic which is the ultimate forcleaning; yet, these items can more easily be cleaned than replaced bythe hospital and a great deal of supposedly sterile devices have beencontaminated at delivery which is highly undesirable for the patient. Onthe other hand, many industrial production procedures in use todayprovide precisely heated, extremely uncontaminated fluids, at exactlyrequired volumes and pressures to closed retorts or to processingreactors; yet, there is no known system of irrigation in use in themedical field which is as accurate as these industrial systems.

B. Aspiration--(Which is the removal by suction of air or fluid from abody cavity from a region where unusual collections have accumulated orfrom a container.)

As has been mentioned in our U.S. Pat. No. 3,990,452 the use ofaspiration to remove fragmented dissolved or particulized biotissues isextremely old dating back to the Majima regime in Japan in A.D. 600.Aspiration or the removal of fluids from body cavities by use of anaspirator or the drawing or removing by suction can readily and withoutadditional explanation be seen to be the application of a simple vacuumtechnique or more preferably and precisely the use of negative pressureto a tube, hose, needle, cannula, et al. Such negative pressure (vacuum)obviously has precise and exact limitations, ultimately reaching at itsmaximum 14.7 lbs/in² (1033.5 gms/cm²) or converting to a more usablestandard gauge, 33.9 feet of water (29.91 inches of Hg) at 0° C. and sealevel.

There are many obvious methods for achieving relatively low pressuredifferentials or variations from the 29.9 inches of Hg standardpressure, down to the 0.1 inches of Hg required for use in medical workor in any usage of suction required for successful removal of fluidsfrom the body cavities. Ultimately, however, since the limit of allmethods are dependent from the atmospheric air pressure at sea level,they are in turn dependent upon the gravitational force; in other wordsgravity--applied to the air mass existing at the operating site of theaspirator--such pressure is therefore primarily a physical phenomenon ofthe terrestrial environment.

Generally, medical aspiration of body cavities can be accomplished withthe so-called "low vacuum" range of low atmospheric negative-pressures,i.e., 14.7 lbs/in² (1033 gm/cm², or 10 torr) down to 1/76 th of anatmosphere, or 0.193 lbs/in² (13.59 gm/cm²); in other words, -750 mm Hg(-29.52" of Hg). (All pressures will be indicated in mm of Hg airpressure at 0° C. and sea level, and flow rates inml/second--milliliters per second).

Since 1 torr=1 mm of absolute pressure, a negative-pressure of 10 torr,"low vacuum", would equal -750 mm Hg (-29.52" Hg) which can be readilyobtained with most mechanical pumps of the piston, roller, diaphragm,vane, peristaltic types, and no vapor pumps are required.

Many types of mechanical pumps have been used for creating thenegative-pressures used for evacuating body cavities, however, all ofthese do not have equal desirability for medical usages, as will be seenlater.

C. Medication--(The act of medicating a medical substance or medicine totreat diseases by the giving of drugs; to impregnate with a medicinalsubstance.)

There are many widely scattered devices used for biotissue medicationwith the simplest, and most often used, being the standard medicalsyringe with a regular needle as its injector/applicator. Very littleprior art exists for the simultaneous application of ultrasound andmedication in the patented art.

In our invention, direct sonification is administered to the patient byway of the direct application of the tool of the invention into thetissue. In contrast, in heart/lung machines, medicine is delivered tothe machine and is then carried by the circulatory system of the machineto the patient, thus, confining its spread to that single path. Thisallows the doctor to use very strong medicines, and even materials whichare not medicines, in the machine which then carries them into thepatient under the severely constrained and positive strict control ofthe doctor. For example, dental drilling using ultrasound sometimes hasused abrasive granules of boron carbide which after application is thenremoved since swallowing such material is not healthy or desirable.Another example exists in closed cycle anesthesia machines.

The present invention describes a unique closed system of flow control,feedback sensing and removal, which allows new usage of simultaneousinjectable medicaments.

D. Power Control--(The control of the time rate of doing work which,since we use watts, is equal to 10⁷ ergs/sec.)

Since in the use of ultrasound, a relatively unknown form of energy isapplied to human tissues, it is very important that the totaltime-power, indicated in scientific units, be known. While the problemof determining the exact power going into the tissue is extremelydifficult and in its early infancy, nevertheless, it is possible toaccurately know the amount of power going into the ultrasonicapplicator. Also, by using proportionality and substitution techniques,the time intensity exposure of the tissue to the radiation level beingapplied can be ascertained.

The prior art nowhere discusses the problem of measuring the true powerin watts into the tissue at the application site.

In the present invention the correlation of a scientific watt,determined by a standard ampere method into a known resistance which hasbeen developed by the inventors, allows more accurate calibrating andtesting procedures for power control.

E. Duration Control--(The control and recording of the time ofapplication of ultrasonic energy.)

The inventors use an elapsed time indicator which records in minutes andseconds the summation of the total time of application of ultrasonicenergy which in turn is a measure of the total ultrasonic exposure time.Then the simple and single most important need is to accumulate thetotal time of application of the ultrasound as it is applied, to achievethe important intensity/dwell time factor. Thus, upon the application ofthree watts of ultrasound for 4 minutes--which constitutes 12watt-minutes--we need to know if this has the same curative or traumaticeffect as 6 watts of ultrasound applied for 2 minutes which also isequal to 12 watt-minutes? The inventors have also developed an operatinghand piece which when used for surgery for example, can be flashautoclaved at 380° F. at 50 p.s.i.--an unusual accomplishment.

SUMMARY OF THE INVENTION

Three separate embodiments are disclosed, with the first being thepreferred one, which comprises the latest and most comprehensive model;the second embodiment is our "transition" system while the thirdembodiment comprises the earlier developmental model.

The preferred embodiment will be primarily disclosed and the transitionand earlier developmental models will more briefly be disclosed.

There are many places in medicine where the use of precisely controlledirrigation and aspiration along with proper provisions for medicationand the applying of curative or surgical ultrasound is required. In theclassic operation for the treatment of the pituitary gland through thenasal passage, it is necessary to use ultrasound with simultaneousirrigation and aspiration to provide this singular method of healing thediseased tissue. In the case of papillomatosis the application ofultrasound energy is the only known cure. In Meniere's disease, theapplication of ultrasonic energy is routinely provided and in severalother medical areas ultrasound is creating speculative results of greatand possible historical significant; as for example, in work on cancer.The use of ultrasound for arterial cleanout, removal of blood clots andwelding of bones are also of extreme interest. Ultransonic energy, whenapplied at various frequencies and intensities for different periods oftime behaves quite differently. Thus, it has been known for years thatultrasound can coagulate or liquify blood. It can also agglomerate ordisperse suspensions in industrial uses. It can heat materials or it cancreate molecular transpiration which drastically cools materials. Someof these phenomena are discussed in the following articles by theco-inventor Murry.

1. Ultrasonic Magazine, Vol. 1, No. 2, Fall, 1973.

2. Wire Technology, May 6, 1974.

3. ChemTech, February, April, May, 1975.

One must be extremely careful in applying ultrasonic energy to humanbeings and, thus, the present invention very carefully monitors andmeasures the application of ultrasonic energy at the time of applicationof such energy as well as accurately controls the pressures andquantities of both irrigating and aspirating fluids.

The present invention includes a preferred embodiment which has 5modular sub-systems, which provide these features.

All systems for instrumenting and controlling a process must providepipes, pumps, heaters, gauges, sensors, linkages, reservoirs, and soforth, as required to make the system work. The system of the presentinvention provides a source or sources of treatment fluids at knownpressures and temperatures and at any selected flow rate required by thesurgeon. It must be variable and controllable, preferably--in 1977--bysome form of remote control. The inventors have discovered that thevariable control presented a real problem and after trying many multipleswitches on the floor, or in the handpiece, or operated by kneepressure, and so forth, it was discovered that the best control would beof a wireless form and, thus, the preferred embodiment uses a systemsimilar to that used to remotely control a TV set. Thus, in an operatingroom it is desirable that all controls needed by the doctor be availablewithout the use of wired connections.

Area l in our system is the Control Area.

As mentioned, the need for controlling the flow rate and its pressureinto the cavities under ultrasonic treatment or surgery is inherent inthe irrigation problem. Different types of apparatuses were tried; thefinal one used a group of standard Gilmore pressure measurers and aninput fluid control valve with a Cartesian diver vent-valve of excellentpressure control features. Thus, by the use of these standard availablepressure/flow controls the input flow pressure and venting pressure canall be determined and controlled. Once these controls are set, they arerelatively trouble free and very accurate. A second more practicalembodiment uses the same principles of the first scientific embodimentbut is decreased in size so as to provide a neat, clean, readily usablepackage at the irrigation input end and throughout the entire system.

With both of the embodiments mentioned above, it is possible to achieveany pressure from 0 to 150 mm of Hg and any flow rate from 0 to 500ml/min, although it is necessary to change tubulation size to achieveall of the rates which might be demanded. FIG. 17 is a chart of the flowrate for one typical tubular material only, since the flow rate willvary with the internal resistance of the materials (i.e., the diameter).It is to be realized that in situ use of one of the embodiments, withfull instrumentation available and regardless of what material is used,the operator can set his chosen flow rate at the desired pressure and itwill stay there indefinitely. It is to noted that a very simplereference level should be, and is used, against which the venting valveacts. This reaction-control, once set, is stable at its setting, so ifthe doctor desires--for safety--a maximum pressure of 54 mm of pressurehe sets his reaction-control at 54 mm and from then on his entireirrigation system will stay below 54 mm of Hg.

In the closed body cavity, as for example, the human or animal eye, theinvention controls the pressure in the particular body cavity undertreatment or surgery by paralleling that body cavity (the irrigation andaspiration chamber) with a "10×" or "Cyclopean" artificial eye, whereinall the sensing of the pressure in the interior or posterior chamber ofthe eye is separately accomplished. Since these two chambers aremaintained in parallel at all times, the pressure will be the same inboth the artificial "10×" eye as well as the actual body cavity. Theefforts of prior systems to control the flow through the eye, so as tomake its pressure constant, have been clumsy, dangerous and extremelydifficult, and accurate control has not been accomplished. The use inthe prior art of a single needle with two ducts, for irrigation andaspiration, which requires a three mm incision has prevented theaccurate control obtained by the present invention. In the presentinvention, two separate ducts in two separate needles, solves theproblem of collapse by preventing wide pressure variations.

The use of the "10×" or "Cyclopean" eye in parallel with the actual eyeprovides a large hydraulic cushion, which bypassing the actual eye,keeps it at whatever pressure it needs at all times as well as providinga constant reservoir of treatment fluid for the actual eye. If theaspirator tubing becomes plugged, then the bypass "10×" eye will keepthe pressure across the eye chamber constant and safe in any event.

The "10×-Cyclopean" eye's (its actual chamber being in reality ismechanical closed chamber into which the bypass fluid flows and exits)allows the exact, innate pressure to be determined by the irrigationpressure, and the flow rate previously selected. The "10×" eye issimilar to a typical, industrial processing chamber control. Mountedonto one end of the mechanical eye, is a unique group of diaphragms,stacked several deep, which are activated by the changing pressures inthe "10×" eye. Mounted on these diaphragms in turn, are N-doped siliconstrain gauges which give very large voltage outputs for the smallpressure changes actually experienced. Since it is desired to maintainwithin close limits the pressure in this chamber, somewhere in the orderof ±2 mm of Hg, the output of these strain gauges are used to controlthe speed of rotation of the aspirating pump-motor, so as to increase ordecrease its speed by small amounts. Thus, since the motor is normallyrevolving at 300 rpm's, its plus or minus rpm variations are controlledand, thus, its ± variations in pumping rate. This can then be used tocontrol the pressure in the artificial eye by a like ±2% or any otherincrement, e.g., ±10% or ±20 mm out of 100 mms (Hg), etc.

Once the input flow and pressure rate desired have been set, theaspirator negative-pressure is set to match it, which then "overrides"this gross setting, based on the minute changes in the artificial eyeand in the actual eye. In operation, once the "Cyclop Control" is on,the variations of the pressure, as noticed by the raising and falling ofthe cornea (in the case of an eye cavity), is imperceptible.

Once the contaminated fluid leaves the eye (or other closed chamber) itis evacuated into a collecting bottle which is kept at the correctnegative-pressure (vacuum) by the pre-selected speed control of thepump/motor. The vacuum level is very precisely held by the "CyclopControl", but should the pressure become excessive, for any reason, aparallel mechanical safety "poppet-vent" is used, which can be set tounload at any desired preset pressure from zero to 380 mm of Hg (15").

Note that the motor has a number of coupling, stepping ranges, providing4 speeds to the pump spindle, any of which may be used to control theaspiration rate, and all of which will maintain these speeds once set,via our "Cyclop Control." This gross speed, 4-step, speed-control deviceis similar to that on a 4-speed phonograph turntable. Once the flow,liquid or air, leaves the collection bottle it goes through a uniqueperistaltic pump which will be described somewhat later, and from theregoes into the recirculating feedback link. Note this is now a positivepressure (after the pump) and is applied as such to the closed cycleirrigation bottle, throttled down to the exact pressure requirements ifneed be. This closed circuit may be broken, if so desired, and operatedat the pressure head of the hanging bottle alone.

Another of the most difficult problems which exists in themedical/surgical field is that of calcified or hard deposits ofconcretion. These are composed of salts of organic or inorganic acids(or of other material such as cholesterol). These form throughout thebody anywhere and everywhere; from the deposits on teeth (dentalcalculi) to those in the pelvis (staghorn calculi) and elsewhere.Knowing these are hardened salts, it should be apparent that they aredissolvable by acids and, with the addition of simultaneous ultrasound,readily removed,

. . and such is the case.

The choice of the correct acids and/or other chemical agents requiredfor each case of calculus deposits is complex, and must be ascertainedby extensive and careful medical research, since the healthy tissuesurrounding the calcified tissue will be readily attacked by anychemical which works on the calculus, because of its highly similarbiological nature.

The inventive method of using two separate needles immediately providesa unique technique of infusory injection of the specific chemical intothe calcified deposits while under the application of continuous, orbursts, of high intensity ultrasonic energy into a narrow confinedregion of the body and in precisely controlled amounts for a period oftime determined specifically by the doctor.

Note, this again ties-in with the not too well known fact that chemicalreactions; (1), speed to completion; (2), take place with far less useof the chemicals (e.g., a 4% solution of hydrochloric acid in thepresence of 25 watts/cm of ultrasonic energy, is as effective, at least,as is 100% of the acid without ultrasound), and indeed, (3), takes placein seemingly impossible ways (e.g., mixing of mercury and water, or oiland water) with ultrasound present. For more on this, see the article ofMurry in Chemical Technology, Vol. 5, February, April and June, 1975,for example.

To accomplish the injection into the body cavities under sonic surgery;"Sonurgy" (a neologism, by choice, which will be trademarked) withprecise control, a "Y" tubulation configuration is inserted into theflow path of the irrigation system. The extra branch contains in it, atiny spincture valve through which infusory micropipette injectors areinserted at the correct time in the operative scenario. By choice of thecorrect size of the metering micropipette, the specific amount ofchemicals (or medicament) placed into the eye or tumor, for example, canbe controlled.

Since one of the most intractable problems in cataract surgery has beenthat of brunescent or senile cataracts, this discovery and method ofeliminating them, is of first importance to surgical intervention (i.e.,intracapsular) in the removal of cataracts. However, it must beimmediately added, that this controlled infusion of medicament is notlimited to use for the removal only of hard cataracts, but can beapplied with success to many other areas of surgery; for example, to theremoval and/or treatment of joint deposits, including that of the spinalcolumn.

Simple, straightforward injection of these chemicals into hardeneddeposits has been tried with some success, but the "plugging" of thecannula or needles used, hindered application. No such plugging takesplace under the presence of the vibrating energy of controlled andsimultaneously applied ultrasound, which not only facilitatespenetration, but literally dissolved a path ahead of the needle as if bymagic.

In addition to ease of high accelerating penetration, free of plugging,the vibrating needle creates intense microstreaming (as set forth inU.S. Pat. No. 3,990,452) vortices, which forces the medicament into thesurrounding hard tissue in the manner of the ultrasonic "ink spitters",used in fast, electrostatic printing. Indeed, cell walls are penetratedwithout damage.

In addition to the need to provide irrigation pressure and flow control,sensitive pressure control and infusion--in the closed body cavity--anda collecting/recirculating module, there is provided a precisepower/time input indicator and a method of recording the total "dwelltime" (i.e., that time during which the ultrasound is applied to thetissue) during which precise amounts of power are used.

Some information on such devices has been disclosed in our U.S. Pat. No.3,990,452. During that earlier period the inventors developed theseinstruments as adjuncts, once the need became apparent, but since then,these units have been perfected and are now incorporated as standarditems. These two devices provide, in turn, an Elapsed Time Meter and aWattmeter, which later reads the true ultrasonic power going into thehandpiece by integrating the voltage and current (at 40 kHz) as it isapplied. In other words, application of the handpiece tool to tissue,once tuned to maximize its wattage input, reads the correct real powerinput fed to the handpiece. With this reading, and some minorcalculations, one can tell, if not "how", at least, "how much" 40 kHzpower is being applied to the invaded tissue. (Please note: since agreat deal of the input power goes into the lavaging fluid and iscarried away as heat, one cannot know how much really goes into thetissue, but only how much it is maximally exposed to.) Since every timethe remote control, wireless foot switch turns on the ultrasound, theE.T.I (Elapsed Time Indicator) runs, and accumulates the timesequentially, we also know the total intensity/dwell factor for any oneoperation, i.e., the exposure of the invaded tissue to radiation for ameasured period of time.

These main features disclose the invention in its interrelatingcomplexity, which will be amplified hereinafter; however, certain otheradditional features of the invention will be disclosed, since they makethis invention in combination with what is shown in our U.S. Pat. No.3,990,452, a truly highly sophisticated medical device of unique scopeand implication for the medical profession.

It has been the goal of the inventors to develop a method of putting thepotentials of ultrasound into the services of medicine. This has beendone, and shall be continued, and, it is to be understood that we didnot, and do not, wish to merely make an "Eye Machine", an "Ear Machine","Bone Machine", etc., but a universal, highly scientific reliable,effective ultrasonic energy device, which the vast majority of surgeonscan use in their own specialties, with confidence, ease, and in theservice of man. Therefore, we also disclose the following additions toour device.

There has been also added to this system a unique feature to thehitherto passive (ultrasonically speaking) irrigation needle, a quitesmall (in cross section) handpiece, about 3/8" in diameter, which mayremain passive, be activated alone, or be activated in conjunction withthe main operating probe during the irrigation/aspiration time. Thisdevice is of considerable use to the doctors in and during operations,usually working in conjunction with the other probe.

Other objects, features and advantages of the invention will be readilyapparent from the following description of certain preferred embodimentsthereof taken in conjunction with the accompanying drawings, althoughvariations and modifications may be effected without departing from thespirit and scope of the novel concepts of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall system view of the scientific flow system concept;

FIG. 2 is an overall view of the preferred practical embodiment;

FIG. 3 is an overall view of a transitional modification;

FIG. 4 illustrates another earlier modification/embodiment;

FIG. 5 is a complete operational diagram of the electronic circuit usedin the independent aspiration/irrigation systems;

FIG. 6 illustrates an early model of a vacuum leak;

FIG. 7 is a drawing of an advanced model simultaneous pressureleak/vacuum leak, single valve system used in the preferred embodiment;

FIG. 8 is a sectional drawing of the unique peristaltic pump and motoranti-reversal system;

FIG. 9 is another view of the peristaltic pump showing rollers andspring lock;

FIG. 10 is another view of the offset and camming of the peristalticpump;

FIG. 11 is a sectional drawing of a shutoff for the passive handpiece;

FIG. 12 is a sectional drawing of still another shutoff for the passivehandpiece, with micro-pipette syringe injector part;

FIG. 13 is a block diagram of the transmitter part of the ultrasonicsystem for wireless control of the various subsystems;

FIG. 14 is a block diagram of the receiver part of the ultrasonic systemfor wireless control of the various subsystems;

FIG. 15 is a schematic drawing of the ultrasonic transmitter system;

FIG. 16 is a schematic drawing of the ultrasonic receiver system,showing control relays;

FIG. 17 is the flow rate chart for 1/8", silicon tubing at variousreadings of the valve settings of the flow meter; and,

FIG. 18 is a view of a modified Gilmore type, pressure control valveused herein.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is an overall view of the scientific configuration of the mainfeatures of the invention with certain subassembly portions of theinvention put together so as to clarify the explanation of the maininvention. The left portion of the drawing discloses the irrigationportion 34 and the right portion of the drawing relates to theaspiration portion 36. In the irrigation portion 34 a stand 10 has abase 11 and an upright member 12 which is provided with calibrations 13which can be calibrated in both inches and metric units, thus,permitting whatever units are required to be used. A sliding clamp 14can be locked with a set screw 16 and has a supporting hook 17 whichsupports a hanging bottle 18 that can be adjusted to any height bymoving the clamp 14. A shut-off clamp 19 is placed below the bottle 18on the supply tube 20. The bottle 18 may be adjusted in the relativerange from 6 to 30 inches in height or up to 6 feet if it is useddirectly as a floor supported stand. The bottle 18 containing thetreatment fluid may be 1, 2, 3 or more liters in capacity as requiredand is completely sealed from airborne contamination. Connected to theupright stand/bottle system is a length of tubing 20 made of silicon,polyethylene, teflon or other plastic as desired and of a suitablelength. The tubing 20 is connected to a flow meter/flow control 21 whichmay be a modified Gilmore flow unit type 390 capable of indicating andcontrolling the flow of the treatment fluid from 0 to 200 ml/minute. Thespecific flow rate required is controlled by the micrometric taperedchoking control valve 22 which can be manually adjusted. The effect ofthe choking control valve 22 can be observed on the flow indicator 21which is the standard Bernoulli rising-ball type indicator. Our researchhas determined that extremely small variations in flow rates for anygiven size of tubing and input pressures, and for all feasible treatmentfluids having poise ratings of (3-12) C.P. viscosity, can use astandardized indicator ball to indicate the time-flow rate. If thetreatment fluids used are more or less of the same viscosity, asmeasured by a separate indicator, a ball can be selected of the properdensity to suit our needs once the viscosity of the fluid has beenmeasured by a counter-poise gauge.

The flowmeter/flow control valve indicator 21 is tubular connected byfittings 23 and plastic tubing 24, of the same I.D. and pastic materialas selected for tube 20, to a pressure control/gauge 27. We have foundthat this gauge 27 must be modified so as to operate within the range ofthe treatment fluids used and not with the standard mercury usuallysupplied, since it is connected to a fluid source and not to a gassource. FIG. 18 illustrates the modified Gilmore gauge 27 and includesthe ball 327.

Portion 26 of the gauge 27 is a modified pressure head check valve andlower portion 25 is the bottom fluid reservoir; while the knob 28 is thepressure control adjustment which can be varied to change the pressurefrom 0 to 200 mm of Hg (or, since generally a fluid close to the densityof water is used in medical fields, from 0-2720 mm of H₂ O). Byadjusting, the flow indicator 21 by varying its control valve 22 and thepressure control gauge 27, by adjusting the knob 28, the flow rate canbe established at any rate desired, at any pressure desired. This isnovel in the medical irrigation field and gives results which are veryadvantageous.

An output supply tube 31 supplies the irrigation medicating andtreatment fluid to a Cartesian Diver type pressure safety control 29.The principle of the Cartesian Diver control is well known in physicsand the Diver 30 can be controlled by adjusting the knob 32 so as toprescribe an upper limit to the pressure which is available. It is to benoted that the Diver as used herein is in a modified form as apressure-leak instead of the usual vacuum-leak configuration.

FIG. 17 comprises a chart which shows the overall calibration of theirrigation part of the system illustrated at the left in the dotted lineportion on FIG. 1. It is to be observed that for a given size of tubinginside diameter, the flow rate and pressure change can be controlled bythe two controls 21 and 27. Pressure safety control 29 does not become apart of the system until the pressure exceeds the safety level presetinto it, at which time all that the control settings established by knob22 and knob 28 can do, is to adjust the pressure downwardly and neverupwardly above the level set by the safety level knob 32, which providesa very desirable safety feature.

The aspiration portion 36 of the system illustrated in FIG. 1 shown tothe right of the 2nd dotted line in FIG. 1 provides the vacuumnegative-pressure suction and operates with a standard Cartesian Diversafety valve 37 that has an adjustable control knob 38. By varying thecontrol knob 38, the upper safe limit of the vacuum suction can beestablished at any desired figure from 0 to -381 mm Hg (0 to -15" of Hgor 0 to -1/2 of an atmosphere). In normal use, Diver 29 and Diver 37will be closely set to each others range since it is known that theinput pressure and the output vacuum-suction pressure should be at theexact differential needed to maintain the flow rate required withoutcollapsing the chamber in which a medical operation or otherintervention activity is occurring. It is to be noted that in thisapplication it is gauge pressure, not the absolute pressure beingdefined, since the entire system including the controlled cavity 48,which may be a biological cavity, which is exposed to normal atmosphericpressure; in other words, 14.7 p.s.i.

Another tube 55 is connected from safety valve 37 to a standard two holevacuum bottle 39 which has its upper end sealed. The treatment fluid andmicrodebrided material from the biological cavity may then be collectedin the bottle 39. A tube 41 extends from bottle 39 to a tee connectorwhich has a vacuum gauge 42 connected to its branch and which might readrange from 0 to -10" (or 0 to -254 mm) while the upstream output 44 ofthe tee 43 is connected to a larger size of tubing 44 which is passedthrough the peristaltic pump 46 which provides the suction for thesystem. The still further downstream tube 47 at the output of the pumpwill have a positive pressure equivalent to the negative pressure intube 44 before the pump 46. The tube 47 is fed back to the hangingbottle 18 and thus a closed sterile system is provided. It is to benoted that it is gas pressure downstream not liquid pressure and nopostpassage contamination of the sterile treatment fluid in the hangingbottle 18 is possible.

In FIG. 1, a simulated biological test chamber 48 is illustrated and oneof the main features of the invention is that an artificial cavity 49 of10 times the size of the artificial or biological cavity 48 is placed inparallel with the test cavity 48 or a biological cavity and thesecavities are interconnected by tubes 51 and 52 as shown. In thisinvention, particularly in the case of eye work, and in this arrangementwe designate the 10× cavity 49 as a Cyclops eye, for obvious reasons.The large cavity 49 sees or experiences simultaneously the same pressurevariations that the anterior chamber of the eye or other body cavitydoes, minus some very slight pressure losses. If the pressure in abiological chamber 48 raises or lowers plus or minus an amount of10%--usually 1%--the 10× chamber 49 also experiences a similar pressureincrease or decrease and sensing diaphragms 57 mounted in a housing 56distend or contract accordingly since the stacked diaphragms are exposedto this pressure variation. It is to be realized, of course, that inputtube 53 is connected to the chambers 48 and 49 and output tube 54extends from the pressure control 37 to the chambers 48 and 49.

The diaphragm 57 is enclosed in a sealed chamber 56 which can be openedto atmosphere (or in the case of an anterior chamber of the eye to thesame ambience) or to positive or negative pressures as desired and thediaphragm can be set to respond to any range or pressure operationsdesired. Generally, the exterior surface of diaphragm 57 will besubjected to atmospheric pressure.

Attached and firmly bonded to diaphragm 57, or connected to it, is apressure-to-voltage transducer 58 which may consist of N-doped siliconformed into a strain gauge, or alternatively, may consist of a linearpotentiometer. The transducer 58 functions to convert minute variationsin the distention or contraction of the diaphragm-bellows 57, caused bypressure variations, into voltages which are fed to a voltage controlledoscillator/amplifier 61 through lead 59 which provides fine speedcontrol for the motor which drives the peristaltic pump 46.

A motor 62 receives the output of the oscillator/amplifier 61 and themotor 62 may be a Molor type 12 pole 60 cps motor which normally rotatesat 300 RPM. When it receives from amplifier 61, 54 to 66 cycle currentthe speed of the motor will vary from 280 to 330 RPM or plus or minus10% around its normal means speed of 300 RPM. This will produce apronounced effect on the delivery rate of peristaltic pump 46 to whichit is connected by fixed gearing 63 and shafting 226 as shown in FIG. 8.

Thus, FIG. 1 illustrates the basic operational concept of the inventionwhich is designed to provide any irrigation flow rate, at any pressure,into a finite biological chamber, along with controlled evacuation ratesof aspiration while maintaining the chambers patency within smalllimits; meanwhile rigidly providing for complete safety of the patient.

FIG. 2 is a practical embodiment of the apparatus illustrated in FIG. 1and those parts which are commonly numbered in FIG. 2 correspond tothose having the same numbers in FIG. 1. The stand 10 supports thecalibrated rod 13 in a three footed base 11 and the rod 13 is calibratedin inches of pressure arbitrarily since the pressure gauge 27 iscalibrated in inches of mercury. The clamp 14 is locked in place by setscrew 16 and supports the flask 18 containing the treatment fluid andthe clamp 19 controls the primary on-off flow of the treatment fluid.Feedback pressure is supplied by the pump 46 through tubing 47 which isconnected to the hanging flask 18 by a suitable fitting. The input flowpressure available is again monitored and set by knob 28 on gauge 27 andthe flow is controlled by built-in metering valve 22. The housing 60 ofthe machine illustrated in FIG. 2 contains many of the internalconnections which correspond to those illustrated in FIG. 1. The fluidfrom the hanging bottle 18 passes through the tube 20 into the case 60and emerges from fitting 81 which is connectible to tubing 51a ofhandpiece 73 which has a needle 70 that can be inserted into a suitablechamber such as an eye 75. The handpiece 78 has an aspirating needle 79which can be inserted into the eye and a tubing 52a is connectible to afitting 82 which is internally connected to a tube 55 which is connectedas shown in the drawings to the collecting flask 39a. Flask 39a isexhausted to a desired vacuum negative-pressure as indicated on gauge42, which is also internally connected by a suitable tube not shown fromthe tube 41 to the gauge 42 at "X". The tubing 41 is connected to tubing44 and internally to dual pressure leak/vacuum leak 66 which will bedescribed later. The pump 46 provides pressure in tubing 47 which isused to repressurize hanging bottle 18 through the tubing 47. The 10×artificial chamber 49, the sensory diaphragm 57 with its housing and thepressure sensor 58 and the voltage-to-frequency converter 61, as well asthe low RPM drive motor 62 and the four-step speed changer 63 are allmounted inside the case 60. The speed-change lever 65 is connected tothe speed changer 63 and extends from the case as shown to allow themajor speed ranges to be adjusted.

Certain items which are shown in detail in U.S. Pat. No. 3,990,452 arealso mounted in the case 60. These are the true reading wattmeter 68. Aknob 69 controls the frequency of the ultrasonic oscillator as set forthin U.S. Pat. No. 3,990,452 and its correct tuning is indicated by thedimming of amber light 50 and the peaking of the wattmeter 68. The levelof power desired is of course selected by the push-button system 71while the elapsed cumulative time of application of the ultrasound iscontinuously recorded on elasped time indicator 65.

The preferred and practical embodiment illustrated in FIG. 2 shows a newfeature of great use; the dual ultrasonic output available at terminals71 and 72, marked L and R, and controlled by switch 73. The switch 73 isa three way switch permitting sonic energy to be available at jacks 71and/or 72. Handpiece 73 is shown with a bent irrigation needle supplyingfluid from the hanging bottle 18 but it may be replaced by simply astraight irrigating needle or a "butterfly" needle and may not furnishultrasound if so desired. If ultrasound is to be supplied, theultrasound supply cord 74 is provided with a suitable plug for insertinginto output socket 71. In the configuration shown handpiece 73 may beprovided ultrasound energy from socket 71 and irrigating fluid fromtubulation fitting 81. This handpiece further includes a spincture valve77--shown elsewhere in FIG. 12--which is normally closed but which isavailable for inserting micropipettes for injecting or infusing specialfluids such as needed for dissolving stones, deposits or cataracts. Aslide valve 76 provides control of the treatment fluid applied to theneedle 70. The needle 70 may be in a variety of shapes and gauges fordifferent types of operations and purposes.

The second handpiece 78 is of the form illustrated in U.S. Pat. No.3,990,452 and has an instrument 79 affixed such as the tip illustratedand receives ultrasound through the cable 83 which may be inserted intothe socket 72 and is provided with an aspirating tube 52a which isconnected to the aspirating fitting 82 of the machine 60 so as toprovide aspirated fluid to the bottle 39a.

A pressure-leak/vacuum-leak control (PL/VL valve) 66 comprises a newfeature of this invention and will be described in detail later. Forcontrol of the machine and its many features, a wireless remote controlswitch 86 provides control without wires to the machine 60 forcontrolling the machine during the course of an operation. It will bedescribed in greater detail subsequently.

FIG. 3 illustrates an earlier modification of the invention which was ina simpler form and the machine 91 is formed in two portions, anirrigation/aspiration portion 92 and an ultrasonic portion 93. Many ofthe parts are common to those illustrated in FIGS. 1 and 2 and thehanging bottle 18b supplies fluid through a tube 20b and a tee connector99 to tube 51b for providing irrigating fluid to the needle 70 of thehandpiece 73. A separated vacuum leak 122(V/L) and a pressure leak121(P/L) in combination, work similar to the pressure-leak/vacuum-leak66 illustrated in FIG. 2, except each valve 121 and 122 must beseparately set, but once set controls the positive and negative-pressure(vacuum) available. The foot switch 94 operates similar to the wirelesscontrol 86 which is, however, a remote R.F. transmitter, while in themodel illustrated in FIG. 3 a cable 96 hard-wire connects the control 94to the machine 91. The control 94 controls: (1), 271 irrigation; (2),272 aspiration; and (3), 273 ultrasound. Ultrasound can be availableeither alone, at one of the two handpieces 73 or 78, or at bothsimultaneously as determined by the setting of switch 73. Ultrasound isapplied to the handpiece 73 through cable 74 and plug 74a which can beinserted into socket 71. A redundant grounding plug 106 can be insertedinto socket 108. Ultrasound for the handpiece 78 can be supplied throughcable 83 and plug 112 which can be inserted into socket 72 and groundingplug 114 can be connected into redundant grounding socket 116.

FIG. 4 illustrates a still earlier modified embodiment wherein themachine 136 included many elements common from the system disclosed inU.S. Pat. No. 3,990,452 including a single aspirating handpiece 78 witha needle 79 and an ultrasound supply plug 112 and grounding plug 114receivable in sockets 72 and 116 respectively to supply ultrasound tothe handpiece 78. A frequency control knob 69 allowed the frequency ofthe ultrasonic generator to be adjusted while an aspirating tube 52b isconnected from the handpiece to a peristaltic pump 46 which provides anoutput through tube 41b to the fluid collecting bottle 131. A wattmeter68 and an elapsed time meter 65 are provided. A simple V/L vacuum leak122a is provided as is a large vacuum gauge 42 for measuring the degreeof vacuum in the aspirating line 52b while the power selector switches71 and dimming amber light 50 indicates the selected power level is atpeak. The peristaltic pump 46 provides the aspirating evacuation for thehandpiece 78 while the microdebrided material is collected in collectorflask 131 which might be a plastic bag. A 5 to 8 micron replaceablefilter 100 is placed between the tee connecting joint 95 and thegauge/vacuum leak 42 and 122a to prevent debris from contaminating orplugging these components.

Thus, the apparatus illustrated in FIGS. 1 through 4 comprises variousmodifications of machines which have been reduced to practice and used,as for example, in cataract operations.

In our U.S. Pat. No. 3,990,452, FIG. 12 thereat, is illustrated awattmeter 107 and the elapsed time indicator 108. FIG. 10 of that patentillustrated the internal connections, including the ultrasonicgenerator, to the handpiece.

FIG. 5 hereat illustrates the new added circuit using a type MC1495Lintegrated circuit 171 which together with integrated circuit 176generates an output voltage V_(out), which equals KV₁ V₂, which causesoperation of our true reading wattmeter 68.

"K" above, is a gain factor which is set for the proper rangecalibration of the meter. The voltage which is applied to integratedcircuit 171 at the junction between resistor R1 and the integratedcircuit is derived from the voltage which appears across the handpiece78 (the microdebrider probe). The voltage V₂ is a voltage derived fromthe load current into the handpiece 78. Since these are at all times inproper phase, voltage times current is equal to watts and the powermeasurement is indicated on the meter 68.

The elapsed time indicator 65a is a synchronous Veeder-Root typemultiple-disc counter driven by a 60 cycle clock motor (not shown). Inorder to operate this device so as to make it indicate when ultrasonicenergy is being applied to the biotissue, it is necessary to apply 60cycle, 120 volt power to the Timer's motor, coincidence with operationof the foot switch 94 which has in it two spring-loaded make-contacts.In the partially depressed position switch 94 turns on the pump 46causing suction to appear. Fully depressing switch 94 to its bottomposition, causes the ultrasonic generator to produce 40 kHz energy. Aportion of this is picked off and amplified by transistor Q₄ in FIG. 5and this output is then coupled through transformer T₂ and supplied to atriac Q₃ which acts as a switch to turn on the timer 65a. In this manneronly, and positively, when ultrasound is generated is time logged onthis accumulating meter which is necessary and desirable as pointed outpreviously. Thus, a simple need to turn "on" and "off" AC 60 cycle powerhas been refined to directly record the time/dwell factor of theultrasonic energy which is present.

The double vacuum-leak/safety device illustrated in the embodiment ofFIG. 4 is shown in detail in FIG. 6. The pump 46 in FIG. 4 can pump to anegative pressure of -15 inches (-381 mm) of Hg which is far too muchfor use in many parts of the human body, especially the human eye.Hence, it is necessary to provide safety factors at every step of theprocedure. By utilizing the proper thickness of tubing wall in theinternal interconnecting tubing for example--one which will collapse andclose off the pumping at a negative pressure--an upper limit of -15inches of Hg can be obtained for example.

FIG. 6 illustrates a distribution block 181 which is a solid drilled-outpiece of brass connected internally so as to interconnect the gauge 42,the suction output 82, the hose 186 & 187 which collapses at a -15inches of Hg and the double vacuum-leak 122. When negative pressure isapplied by the pump 46 to the tubulation of the system and the feed tubefrom the handpiece is pinched-off at "Z" on the tube 52b which goes tothe handpiece 78, the gauge 42 will read the full head negative-pressureof the pump 46 which is normally about -29.92 inches of Hg. However,this will only be allowed to reach -15 inches of Hg due to the collapseof the tube 82 at -15 inches and then only if vacuum leaks 198 and 189are screwed completely in.

Further break points are set in by adjusting the leakvalve 189 and 198which consists of a body of hard plastic 192 and a pair of safetysprings 193 and 194, two ball bearings 196 and 197 and a pair of stems191 and 205. O-ring seals are used on each stem to seal off the stem soair can only enter the inner chamber 201 through the leak holes 206 and203. In operation, the front valve 198 is closed down completely bymeans of an external knob(not shown), but which is the same as knob 122bshown for valve 189. When valve 198 is completely closed, a pinching offpressure is applied at "Z" on the tubing 83b coming from handpiece 78.Then high limit valve 189 is adjusted with knob 122b until the vacuumgauge 42 reaches the desired upper-set limit usually -10 inches of Hg.Since this adjustment is inside the case 136 and sealed at the factorythe negative-vacuum pressure will never exceed -10 inches of Hg sinceany suction on fitting 200 will appear in the chamber 201 and cause theball 197 to unseat at -10 inches of negative pressure, thus, allowingair to leak into chamber 201 through the leak hole 203.

Once this is set and sealed internally, the front panel knob connectedto shaft 204 must be adjusted in a like manner to the operating pre-setnegative-pressure desired, usually -3 to -5 inches of Hg (-76.2 to -127mm of Hg). This is varied as needed during the course of the operationand the doctor can obtain zero to a maximum of -10 inches of Hg via thiscontrol.

In the embodiment illustrated in FIG. 3, two leak valves similar inoperation to that illustrated in FIG. 6 are used, however, one valve isa pressure-breaker valve or a "pressure leak". The principle of thepressure leak/vacuum leak valve is illustrated in FIG. 7.

The right side of the apparatus in FIG. 7 comprises the vacuum valveillustrated in FIG. 6 and operates as previously described. In thisvalve, however, only a single knob 207 is used which operates so as tosimultaneously control the low levels of vacuum and pressure required.By rotating the thumb wheel knob 207 so that it moves to the right, weincrease the amount of negative pressure required to make the ball 209move from its seat 212 while at the same time lowering the amount ofinput pressure required to move the ball 213 off of its seat 216. It isto be noted that rotation of the knob 207 causes the shaft 230 to moverelative to the housing 206 due to the threads 235 which accomplish thisresult. Thus, a differential action of great sensitivity at the lowerranges of pressure and vacuum are obtained which are necessary inbiological work.

Thus, the doubleacting valve 66 may be placed across the artificial 10×X cavity or chamber and its diaphragm can then be delicately set to thezero level or other level required. This same valve can also be used fordifferent pressure ranges and/or vacuum ranges by simply changingsprings 214 and 211 as needed and the ranges of the two valves need notbe the same.

The unique floating peristaltic pump 46 is illustrated in FIGS. 8, 9 and10. In FIG. 8, the motor 62a has an output shaft which is connected to anylon gear 222 which is connected by toothed engagement 63 to nylon gear224 which drives the peristaltic pump shaft 226. The motor 62a may be a12 pole magneto-ceramic core motor which turns synchronously at 300 RPMif 60 cycle power is applied. Since the speed is low, it is possible touse a single pair of nylon gears to reduce the RPM to that required forthe flow rates of 25 ml to 200 ml per minute with great ease andefficiency. By utilizing a large diameter shaft 226, a highconcentricity is obtained with anti-reverse bearing 227 while excellentclutching action is obtained. Bearing 227 is a dual acting rolling-pinbearing with a built-in no-reverse clutching action which is required sothat no possible reversing of the motor can take place, thus absolutelypreventing return of all debrided material back into the eye or otherbody cavity. The bearing used is a standard Torrington type DC thin-cup,roller-clutch bearing and is highly effective. Thus, the advantages oflow RPM is obtained with a few gears as is a positive no-reverse featurenot previously available.

A major breakthrough in a peristaltic pump design has been accomplishedin the present invention and is one of great importance because we havediscovered that the major disadvantages of peristaltic pumps of theprior art is that of the head spacing. In other words, if the spacingbetween the rotor 237 and the clamping head 250 is too small theperistaltic pump acts as a perfect shoe-type brake, overheating themotor and seriously wasting motor power; while, if the spacing is toogreat, the pump will not pump at all or pump only slowly, intermittentlyand inadequately.

We have discovered that by rotating the head 250 to an offset angle of12° relative to the rotor center, as illustrated in FIG. 9 and by usinga camming action at pivot point 236 that the head spacing can beuniquely adjusted--over the proscribed action area--of plus or minus0.010 inches, thus, providing an adjustment for any variations in tubingsize which heretofore can be a constant cause of trouble. Furthermore,an additional springing action is applied at 238 by the adjustment of aknob 239. A swivel joint 235 is provided for opening while 238 containsa spring around its enclosed shaft 241. The spacing between the head 250and the rotor 237 can be accomplished by adjusting the cam 242 which isan eccentric cam. This cam 242 should be adjusted with the spring 238uncompressed by turning the knob 239 until no pumping occurs with thetubing 228 in place in the pump. Set screw 243 is then locked down tohold the eccentric cam 242 in position, then the knob 239 may be rotatedto tighten the spring 238 so as to increase the pressure on the tubinggradually as the shaft 226 rotates. It will be observed that the pumpwill begin to take hold and the vacuum gauge needle will begin to bouncewhich will occur at a relatively low reading and frequency. Furtherturning of the knob 239 will cause the gauge's bouncing to graduallydecrease and the gauge will begin a steady climb to a higher negativepressure; in other words, vacuum level. Putting slightly more pressureon the spring by turning the knob 239 still further and all bouncinessof the gauge needle will completely disappear and a clean steady climband negative-pressure will be achieved. One additional slight adjustmentof about one-quarter turn and the gauge will be precisely set and thepump will be pumping evenly and solidly with a slight reserve pressureon it.

Observation of this action with the tubing in place will show that thespring 238 is causing the swing-head 250 to bounce upward and downwardcontinuously as the rotor 237 is turning and the tubing is beingalternately compressed by the five rollers 265a through e. The pulsatingaction is very smooth and no braking action exists. Furthermore, anysolid debris coming into the tubing acts against the compression ofspring 238 and passes easily through the pump. The secret of the successof the pump is in the 12° offset and the "bouncy" spring 238. The pumpis silent and smooth operating at all speeds and is practically failureproof.

The handpiece 73 illustrated in FIG. 3 provides a new approach toirrigation and is generally used with a two needle technique ofsimultaneously but separate irrigation/aspiration and has greatadvantages over the one needle, two duct, technique of the prior art.Two needles have great advantages particularly when working within tinychambers as small in volume as 0.4 to 1.2 cm³ as in the human eye. Wehave discovered that two needles of one mm diameter would produce lesstrauma in the human body than a single 3 mm double needle. As a matterof fact, it is always desirable to simultaneously use a number of tinyneedles in preference to a single large needle since, if far enoughapart, the trauma caused by the tinier needles would be separatelyexperienced and not cumulative. In any case, a dozen tiny punctureswould heal much faster than a single large equivalent penetration.

The handpiece 73 may be provided with an irrigating close-off valve andan injection spincture port for applying medication directly into thechamber being invaded. It is obvious that the forceful injection ofdissolvents by means of an inserted pipette will put the medicamentdirectly into the area desired and nowhere else.

FIG. 11 illustrates a lever-type action for handpiece closure while FIG.12 shows a roller-type closure. The handpiece 244 has a main bodyportion 247 which is made of plastic and has a central opening 248formed through it, through which 1/16th inch I.D. silicon tubing 249 isinserted. On the end of opening 248, a tapered recess 252 is provided inwhich a collar-button type fitting 251 is placed. When a standardthreaded adapter 253 is screwed into place, the entire assembly locks-upas shown and is then air and liquid tight. Lever 254 is pivotallyattached to the housing 247 and is an offset type lever which whenpulled backwards acts to pinch off the fluid flow by compressing therubber tubing 249 in opening 248 at point 256.

In FIG. 12, which discloses another close-off embodiment 246 with acentral opening 248 and through which tubing 249 extends, a roller 257is slidably supported by a shaft 258 and can be moved rearward anddownward to pinch off the tubing 249 at point 256 to prevent fluid flowthrough the tubing. Additionally a sphincture port structure 259 isprovided to receive a pipette needle 264 therethrough. The injectionpipette needle is sealed with a compression nut 262 and an O-ring seal263. This needle supplies the medicament or dissolving fluid from thepipette when the pipette plunger (not shown) is depressed. This willapply the medicament under pressure to the desired location at the endof the operating needle of the handpiece 246 through tubing 249 ifroller 257 is closed down.

When the handpiece 73 is used for suturing with microsurgery needles,sizes 10-0 to 5-0, use is made of a split needle holder. The needle canbe picked up with the left hand, positioned correctly with the point ofthe right handpiece needle and placed adjacent the tissue to be sutured.A single slight burst of ultrasound, achieved by touching the footswitch briefly to on, will cause the suturing needle to vibrate at40,000 times per second and enable it to immediately penetrate thetissue with great ease.

FIGS. 13 and 14 illustrate the control system used. In FIG. 3 it is tobe noted that the switch 94 has three direct control elements 271, 272and 273. Each separate actuating switch lever clicks on and then clicksoff and no element of fatigue is present since it is not necessary tohold the foot fast against any of the switches. In the embodimentillustrated in FIG. 3, the switch 94 is hard-wired by the cable 96 tothe medical device 91 and the remote control ultrasonic transmissionfeature is not used but the same controllable items are actuated and,thus, the description of switching for both the model illustrated inFIG. 2 and FIG. 3 can be simultaneously described.

When switch 271 is pushed to the left in FIG. 2, an internal valve willactivate and connect it between the pressure gauge 27 and the handpieceoutput fitting 81 which will now be opened and irrigation fluid willflow from the hanging bottle 18 since the hanging bottle 18 is at ahigher point than gauge/adjustor 27. This static head pressure will beread on the pressure gauge part of 27 and may be set, if so desired,when running with an opened irrigating bottle. Pushing the switch 271again will turn the treatment fluid off and so forth. The "off"condition will be noted by the pressure indicating ball in gauge 27dropping to the bottom of its tube.

When switch 272 in FIG. 2 is lightly touched by the foot, theaspiration, which includes the vacuum pump 46, will be energized andturned on at a preset speed determined by the position of control lever65. Thus, irrigation or aspiration or both can be selected by use of thefoot by simply activating the switches 271 and 272.

The central switch 273 of the foot switches 86 and 94 in FIGS. 2 and 3will turn the ultrasonic power to the on condition but will continueonly as long as the switch 273 is depressed. Thus, power will appear atsocket 71 and/or 72 depending on the position of the switch 73. When thepressure is removed from switch 273, the ultrasonic power will bedisconnected from output sockets 71 and 72.

In our work in operating rooms, it has been observed that theelimination of entangling cords, tubing, wires, et al is very desirableand therefore a foot control switch which rests on the floor immediatelyavailable to the doctor's foot and which has no attachment wires is verydesirable. This unique switch shown in FIG. 2 includes the switches 271,272 and 273 but the wireless switch 86 includes an ultrasonictransmitter for radiating control signals to the medical unit 60 ratherthan via the hard wiring as shown in FIG. 3.

FIGS. 13 and 14 disclose the transmitter and receiver respectively, forthe system.

As shown in FIG. 13, the transmitter for the remote control comprises anoscillator 282 which receives an input from a battery E and includes amonitoring meter 281 to show the condition of the battery while amovable contact 283 of a multiple switch is engageable with fixedcontacts 284, 285, 286 and 287. 284 is a contact which when engaged byswitch contact 283 turns oscillator 282 off. Contacts 285 through 287energize the oscillator at different output frequencies which correspondto different control functions of the equipment. The output of theoscillator is supplied to an ultrasonic transducer 288 which radiatesthe energy provided by the transmitter.

FIG. 14 comprises a receiver and includes an ultrasonic transducer 291which detects the ultrasonic energy radiated from the transducer 288 andsupplies it to an amplifier 292. The output of the amplifier is suppliedto a frequency detector 293 which detects a first frequency and suppliesan output to control the aspirator control 297. A second frequencydetector 294 detects a second control frequency and supplies an outputfor the irrigation control 298. A third frequency detector 295 detects athird received control frequency and supplies an output for theultrasonic control 299. The receiver 290 may be mounted inside themedical unit and no cables need extend between the transmitter and thereceiver.

FIG. 15 illustrates an electrical schematic for a transmitter using acrystal ultrasonic transducer for short range radiation. The transistoroscillator 302 receives an input from battery E while the meter 304indicates the condition of the battery. The output of the oscillator 302is sent through a transformer 306 having a high Q to a plurality ofcapacitors C30 through C33 via relays. Switches 307 and 308 are gangedtogether and switch 307 turns the oscillator 302 on in three positionsas illustrated in FIG. 15. Switch 308 connects different valuedcapacitors C31 through C33 in parallel with the transformer 306 tocontrol its frequency and the output frequencies correspond to differentcontrol functions. The transducer 303 is driven through a smallcapacitor C34. Typical frequencies used could be 19.25 kHz, 21.75 kHzand 23.25 kHz at approximately a 0.1 watt level or less. The meter 304indicates when the battery E needs charging and when power is on.

The receiver is illustrated in FIG. 16 and includes a receivingtransducer 307' which has one terminal grounded and the other terminalconnected through a capacitor C36 and an inductance L10 which is coupledfrom a tapping point through another condensor to an operationalamplifier 308'. Second operational amplifier 309 is in cascade with theoperational amplifier 308'. Tuned indicators 311, 340 and 345 arecoupled to the output of operational amplifier 309 and resonate atdifferent frequencies and supply outputs to drive relays 320, 325 and330 which control switches Sa, Sb and Sc respectively, which correspondto the controls associated with the respective frequencies andfunctions. The resonant circuit 311 comprising the capacitor C20 andinductor L10 might be tuned to frequency 19.25 kHz, which is applied tothe base of the transistor 310 to drive the relay 320. The tuned circuit340 comprising the capacitor C11 and inductor L11 may be tuned to 21.75kHz which is applied to transistor 313 which energizes the relay 325 toactuate the switch Sb. The tuned circuit 345 comprising the capacitorC12 and the inductance L12 may be resonant at the third frequency of,for example, 23.25 kHz and this circuit supplies an output to transistor312 which drives the relay 330 to actuate switch Sc.

It is seen that the invention provides a novel medical machine andalthough it has been described with respect to preferred embodiments itis not to be so limited as changes and modifications may be made whichare within the full intended scope as defined by the appended claims.

We claim as our invention:
 1. An ultrasonic instrument comprising anultrasonic generator, an operating handpiece with a hollow operatingtool and an ultrasonic motor in said handpiece and connected to saidultrasonic generator for operating in bio-cavities, a subsidiarypressure balancing cavity, an irrigation fluid supply separate from andconnected to said balancing cavity, a first tube and a second tubeconnected to said balancing cavity, said balancing cavity beingsubstantially larger than a bio-cavity to be operated within, said firsttube being connected at one end to said balancing cavity and at theother end to said hollow operating tool of said handpiece, said secondtube being connected at one end to said balancing cavity and the otherend being adapted to be placed in fluid communication with the interiorof a bio-cavity to be operated within, automatic means for accuratelycontrolling the input fluid pressure in said balancing cavity, means forremoving fluid connected to said balancing cavity at a point spaced fromsaid fluid supply connection, said first and second tubes beingconnected to said balancing cavity at points located between theconnection points of said fluid supply and said means for removingfluid, and one of said tubes being connected at a point closer to thefluid supply connection point than the other of said tubes.
 2. Anultrasonic instrument according to claim 1 further including acontrol/indicating meter connected between said irrigation fluid supplyand said bandpiece.
 3. An ultrasonic instrument according to claim 1including a second operating handpiece with a hollow operating tool andan ultrasonic motor in said second handpiece for operating inbio-cavities, said ultrasonic motor being connected to said ultrasonicgenerator, said second tube being connected to said hollow operatingtool of the second handpiece and said means for removing fluid includesa suction pump connected to said balancing cavity.
 4. An ultrasonicinstrument according to claim 3 including negative pressure controlmeans between said suction pump and said second handpiece.
 5. Anultrasonic instrument according to claim 4 including a fluid collectingbottle connected between said suction pump and said second handpiece. 6.An ultrasonic instrument according to claim 5 including a feedbackconduit connected between the irrigation fluid supply and the exhaustoutlet of said suction pump.
 7. An ultrasonic instrument according toclaim 3 including a pressure sensing transducer connected to saidsubsidiary pressure balancing chamber, a drive motor connected to saidsuction pump, and motor speed control means receiving the output of saidpressure sensing transducer and supplying an output to control the speedof said drive motor as a function of said sensed pressure.
 8. Anultrasonic instrument according to claim 7 wherein said motor speedcontrol is a voltage controlled variable frequency oscillator and saiddrive motor is an AC controllable motor which operates at a speedproportional to its input voltage and/or current.
 9. An ultrasonicinstrument according to claim 3 wherein said suction pump is aperistaltic type pump.
 10. An ultrasonic instrument according to claim 3including means for establishing a maximum preset pressure in abio-cavity.
 11. An ultrasonic instrument according to claim 3 includingmeans for establishing a minimum preset pressure in a bio-cavity.
 12. Anultrasonic device according to claim 1 including a foot actuated controlmeans including switches for controlling irrigation, aspiration and theapplication of ultrasound to a handpiece.
 13. An ultrasonic instrumentaccording to claim 12 wherein said foot actuated control is hardwired tosaid ultrasonic generator and provides controls for said irrigating,aspirating means and making the ultrasonic energy available on demand.14. An ultrasonic device according to claim 1 which provides ultrasonicenergy to two tools.
 15. An ultrasonic instrument according to claim 1wherein a flexible tube extends through said operating handpiece andincluding a sphincture valve extending at an angle through said bodyportion to said flexible tube and sealing means for receiving a hollowneedle through said sphincture valve for inserting medicant into saidflexible tubing in said handpiece.